Film splicing device



Sept. 30, 1941. c McCLAY I 2,257,182

FILM SPLICING DEVICE File-"i Nov. 15, 1937 2 Sheets-Sheet l INVENTOR Em C .MCCLAY ATTORNEY Patented Sept. 30, 1941 I 2,251,102 memento n'nvrcs may C. McCiay, West Los Angeles, Csiifi. a'ssignor teWarner Bros. Pictures, Inc., New ILL,

ware

a" corporation of Dela Application November 15,1937. Serial No. item My invention relates to a film splicing device for splicing the broken orcut ends of a pair of r'llms together in lapped relation.

One object of my invention is tosmeohani cally remove the emulsion or top surface from a film for splicing purposes.

Another object is to utilize a shearing member in a splicing machine to support a film while removing the emulsion therefrom.

Another object is to remove the emulsion of a film by a slicing action.

Another object is to remove the emulsion from a film at a relatively high velocity.

Another object is to reduce the wear of an emulsion removing element.

Another object ls to reduce the tendency of a film scraping elefilm splice to break.

I am aware of the fact that ments in the form of end mills have heretofore been employed for removing the emulsion or upper surface of a film'to be spliced. However, this type of scraper is necessarily limited in cutting surface to the width of the emulsion to be removed as well as being limited to th number of radial cutting edges or teeth formed thereon. This'often results in a clogged, cutter. necessitating frequent cleaning as well -as=frequent sharpening. Furthermore, because of, the fact i that the film maynot always lie fiat against the supporting surface on which it is'scraped. due to its tendency to curl, thecuttingsurfaces of the end mills cannot be moved in a fiatplane while passingonto the film surface because of the den-- ger of the end mills cutting into the body' of the soft film. Therefore the end mills'must first be. brought over the film surface while out-oi'con-r-v tact therewith; and thereafter moved into contact with thesurface before" being drawn there- The. use o'f' 'sinsle edged blades em". for,

across the supported portion of the film with the periphery thereof in contact wilds-the emulsion surface. Means actuated by the bodily movement of. the wheel are. provided to rotate the wheel whereby the periphery thereof is moved at a greater velocity than the bodily movement of the wheel, resulting ina high cutting velocity.

By helically'forming the cutting of the wheel, a slicing action instead of a scraping action is imparted to each ofthe teeth. resulting in a clean'cut; without the appearance of chatter marks. Furthermore. the useof helical teeth permits a gradual slicing movement of esch'tooth entering into the emulsion or upper surface of the film and permits the cuttingwheel to be passed in a straishtline onto and over the film surface without: the cutting wheel tending to dig into the bodyof thefilm especially when first contacting the edge thereof.

A..splice is madeaccording to my invention by removing the emulsion from the end of one of a pair of films to be spliced, preferably as above described and then over-lapping the ends of those films. cementing the over-lappedends, and

thereafter pressing the films together. over an area less than the overlappedportions; This ac- -tion permits the cement exuded from the pressed portion of the over-lapped films to gather at the extreme over-lapped ends of thefilms', slightly raising them. This insures a generous quantity of cement and therefore a secure bond at the ,tips, and when the cement dries these tips are scraping the emulsion is also disadvantageous in that a single edge wears quickly, necessitating frequent Furthermore a single edge when. moved parallel with the nun surface a tendency to dis intothe film, body due to the drawn onto' the mainbody ofthe over-lapped film with a reinforcing fillet resulting at each over-lapped end. p r

The manner of accomplishing the above and 1 other objects of the invention will be more readiiyund'erstood on reference to the following spec- I ification read in conjunction with the accom- 40.

til- 7 1 8 drawings wherein! i is a perspective view of a film splicing ,device embodying y invention. a

semi-plastic condition of the cellulose derivative of which the film isfformed. thereby causing uneven, scraping or "chattering." According to my invention the which the' emulsion is to be removed'is preferably supported, with its'emulsion surface uppermost. up-

'onashearingmemberusedtoshear theendof,

the'film. Acuttingflwheel having alarse number 1 ofciittifig teeth on 130 mm thereof. preferably" helical in form. is Wile-WWw-i l'ig. 2 is a plan view of the film splicing device. Fig 8 is a'transverse sectional view taken along [islet-Quinta; l 4

4-4 of Fig. 2. I a is a sectional view through the emulsion attachment and is taken along the line a e line H of Fig. 2. I is an enlarged fragmentary and pressurebars and is taken along the of 2r is a transverse sectional view taken along is a longitudinalsectional view taken I view of the v Fig. 8 is'an enlarged sectional view through a film splice made in accordance with my invention.

' a The film splicing device comprises a rectangular base it havingya pair of centrally located and upwardlyextending-projections II and I2.

A hardened steel shear bar I3 extends across the projections, and I2 and is received in and suitably clamped in. slots ;|4 and I5, respectively,

therein. A'second pair, oi'upwardly. extending projections I6 and I! at the back of the base In as well as the projection l2 support a longi- -tudinally extending shaft l8. A pair of film' of a stud 44 and a leaf spring 45 employed in a manner identical with that oi stud 25 and spring 33 of the clamp 20. A shearing knife 48, similar to that of 21, is suitably secured to the under f surface of the plate 40 to co-act with the left hand edgeofthe shearing bar |3to sheara film" supported onithe shear bar I 3 when the plate '40 is'moved downward. ,7 g

The means for removing the emulsion from that portion of'the film which is to be spliced onto another film is inthe form of an attach ment generally indicated at 41 (Figs. 4 and 5).

clamps Hand is provided on either side of the shear bar 13, hingedly supported onthe shaft, Ill. The clamp 28 comprises 'a lower filmfsup+- port plate 2| hinged'tothe shaft ilthrough arms 22 and 23. The plate 2| has a channel24 formed longitudinally thereinto support thefend; of a film to be spliced; Plate 2| is adaptedto be sup-' ported, with the surface of the channel 24 in bar l3, by means "of a stud 25'extending up- 'wardly from the base 'lll and having a bevelled headlfi formed thereon. A shearing knife 21 is secured by screws 28 to the bottom of the plate j 2| and is adapted to co-act with the right hand edge of the shear bar l3v to cut theend of a film a alignment with the upper .surfaceof the shear-'- -'The attachment 41 comprises a guide plate .48

secured to the upper surface of the leftlhand.

pressure pad 43 by screws 58. e A dovetailed guideway 3 5| is formed in the guide plate 48 and ex-.

tends parallel with the shear bar I3. A dovetailed slide 52 is movable along the guideway 5| and has a central projection 53 thereon forming ahandle or knob which may be -grasped by arr-operator and reciprocated along the guideway 1 5|. Thespindle 54of a gear pinion 55 is" Joursupported on top of the' bar I3 when the plate j2|' is moveddownward. Locating pins 14- and I5 extending upwardly from the bottom ofthe'film channel2'4 are adapted to engage a pair of opposed sprocket perforations; in a film supported 1 inthe'clamp' 20 to accurately alignithe ifilm in respect'to another film onto which it isto be spliced5' 'A thumblug 38 extends from the plate 2| permitting'theg-plate to be moved about shaft -A "pressure pad 3|, also forming part of the clamp 28, is independently hingedon the shaft i8, betweenthe; armsv 22 and 23 and has a fiat "surface thereon formed in alignment with the.

channel 24 of plate.;2| 'for'the purpose clamp;

'ingya film in the channel. 'Apertur'es l4 and V "15' in the pressure' pad 3l'are provided to re- "ceiv the'pinsfl4 and '15, re'spectively',when the pad 3| is closed. [A thumb lug 32'is'formed on thefpad 3|, for moving the same about shaft II. (A leaf spring 33 is'secured totheunder surface or the lug 32 by means or'ais r wsl (Fig. 3) and is adapted, when the pressure pad 3|. and

late2l are closed] to extend through an opening 35 formed in the plate 2|. When inlthis 4 position the curved and 350f the spring 33 811- gages the beveled head 26 of thestud 25 to hold the members 2| and 3l-in 'a'clamped position.

"Apressure bar 31," in vertical alignment with .V the'shear bar |3;' is carried bythe pressure. pad 3| through aresilient spring'bar 38 secured tothe' pad 3| by screws 39. Pressure bar '31 is adaptedpwhen the plate 2| andjpressurepa'd 3| are in a closed position to clamp a pair of 811+ I naled in bearlngs formed transversely through the center of the slide 52 (Fig. 5). The spindle 54 is resiliently restrained from longitudinal,

movement by means of a ball 56 provided within "a vertical hole formedin the projection 53 which .ball 56 engages a circumferentialzgroove 54' formed on the spindle 54' and is pressedthereagainst by a spring 51. rigidly secured to the pinion- 55 by means of a screw 59. Thepinion 55 meshes with a gear-rack 68 extending parallel to the suldeway 5| and above the pinion 55. The rack 68' is'supported by the guide plate'48 through au-shaped brackq et 8|. The bracket "6 is secured to the guide 7 plate-48 by screws 62 and is secured tothe rack 68b'yscrews 63. I g

' Cutting teeth 64 are.form ed on'the periphery of the wheel 58. By providing a large number of cutting 'teethor edges, "the wear on each tooth is considerably reduced. It will be noted on refere'ncetto Figs; land 2 that these teeth 64 are cut in a helical formationthus providing a slicing action upon the" upper surface of a film due to the angular "contact of the, cutting edges of the teeth, with the: film whfle passing thereover.

perimposed' cemented films': supported by L the shear "member I3 together to form a splice.

- The clamp' I8 is identical with that of "and comprises a lower film supportingplate 48 hinged to the shaft I8 througharms 4| and'4|-' and has a film supporting channel 42, similar to that of 24 of theplate member 2|, formed therein. Lo-

' I eating pins and I1 areformed'in the channel.

42 to accurately locate a film clamped in clamp On reference to Fig. 4 it'will be noted that,

dueto the fact that thepinion 55 is of-smaller diameter than the wheel 58and'also due to the gear rack fill beingpositioned' above the Pinion 55; the'periphery or the wheel stwin move at a relatively highervelocity than the bodily movement of the wheel 58 and in the ysame direc-'fl tion when the slide 52 is reciprocated.

The operation of the'device 'is as follows; Th film supporting plate 40 .and the pressurepad' 43 i comprising the left hand clamp l8 -areboth raised to a vertical position. The right hand .'pressure pad 3| is'alsoraised and a film to be spliced is placed in channel 24 of plate 2| with the end of the film extending over the shear bar |3.'- It is to be understocd'that'the emulsion surface of thisfllm is to .be uppermost when placed in'the channel 24 and, sinceflthis film will i3. Apressure'pad", similar toth'at 01' 3|, is

; independently hin'gedto the shaft l8 intermediate the arms 4l and'4l'. 1 The plate 4|) andpad 43 are supported and clamped in alignment with .7

be uppermost in the completed splice; the under or1clear surface'thereof will be ce'mentedto the emulsion side of theffilm held inthe'clamp l8.

Therefore it is not: necessary to scrape the film.

The right hand pressure pad 3| is next'lowered in a clamping position to secure the film within the channel"24. The'left hand film supporting plate 40. is then lowered causing the shearing member 48 'to'cut the end of the film the upper edge of the shear bar |3-by means a A cutting wheel 53 is along the left hand edge of the shear bar it. The right hand film supporting plate 2| and pressure pad 3| are then raised, while clamped together by the spring 33 with the sheared film therebetween, to a vertical position. A second film to be spliced is then placed, emulsion uppermost, in the channel 42 of the left hand film supporting plate 40 with theend thereof extending over the shear bar is. The pressure pad 43 is clamped upon this film to secure the same on the surface of the shear bar I3. While in this position the slide 52 is reciprocated causing the cutting wheel 58 to be moved across the emulsion surface of the film clamped in the channel 42 to remove the emulsion therefrom. A film cement is then applied to the cleaned surface of the end of the film supported on the bar it. The last step in the operation is performed by lowering the plate 2| and pressure pad ii together thus bringing the end of the film carried in the channel 24 of plate 2| in overlapped relation with the scraped end of the film supported in the channel 42 of plate it, these two films being pressed together by the presser bar 31 carried by the pressure pad ii. The overlapped films are retained in a clamped position for a period of time sufficient for the cement to dry, thus forming a completed film splice.

Due to the resilient clamping effect of the spring 4! in engagement with the beveled head of the stud M the cutting teeth N of cutting wheel 58 will be moved into engagement 5 with the top surface of the shear bar II before and after traveling over the surface of the film extending over bar It. This action will cause a slight wear on the outer tips of the teeth N, or in other words, will slightly reduce theoverall diameter of the wheel 52 thus automatically producing a sharp edge on each of the teeth ll.

Referring more particularly to Fig. '7, it will be noted that the presser bar 21 is narrower than the shear bar If. Thus when the preaer bar is clamped upon the over-lapped ends of a pair of films IO and .1 with liquid cement provided therebetween, the cement will be partially exuded on either sideof the splice to form lumps II and 8!. Duebothtothefactthatthefilmisina' semi-flexible and semi-plastic condition and also to the fact that the lumps II and I are formed on either side of the film splice, the end ll of the film it as well as the portion ll thereof immediately adjacent the right hand end of the presser bar 31 will be raised slightly with the cement lodged thereunder. This action insures a generous quantity of cement to form a secure bond at the extreme ends of the two films l and 81. Since film cement consists largely of solvents compatible with the cellulose derivative constituting the body of the film, the portions 10 and II of the film II will be drawn into intimate contact with the adjacent portions of the film 01. when the cement dries. Furthermore,

extreme ends of the overl. A film scraping device comprising, a film' clamp adapted to clamp a film to be scraped, means on said clamp forming a guideway, a slide movable in said guideway, a film scraping wheel rotatably carried by said slide and adapted to engage said film with the periphery thereof, means on the periphery of said wheel for scraping the surface of said film, a gear rack extending parallel to said guideway, means on said clamp for supporting said raclnand a gear operatively connected to said wheel and meshin with said rack for rotating said wheel when said slide is moved.

2. In a film splicing apparatus, a stationary shear bar, a film clamp adapted to clamp a film in alignment with, said bar with one end of said film extending over said bar, a slide, means on said clamp for guiding said slide in a path parallel to said bar, a sore wheel rotatably carried by said slide, means on the periphery of said wheel for scraping the surface of said film, the periphery of said wheel being adapted to engage the portion of said film extending over said bar when said slide is moved, a gear operatively connected to said wheel, and a gear rack normally extending parallel to said bar and meshing with said gear to rotate said gear when said slide is moved.

3. A film splicing apparatus comprising a base, a film supporting plate on said base, a pressure pad hinged to said base and adapted to clamp a film on said plate, a stationary shear bar adapted to support one end of said film, means'on saidpad forming a guideway, a slide movable in said guideway, a scraping wheel rotatably carried by said slide and adapted to engage the portion of said film supported by said bar with the periphery thereof, when said pad is in clamping position, and rack and pinion means actuated by the movement of said slide for rotating said scraping wheel.

4. A film splicing apparatus comprising a base, a film supporting plate on said base, a pressure pad hinged to said base andadapted to clamp a film on said plate, a stationary shear bar adapted to support one end of said film, means on said pad forming a guideway, a slide movable in said guideway, a wheel having scraping teeth on the periphery thereof rotatably mounted on said slide, the periphery of said wheel being adapted to engage the surface of said film when said slide is moved, a gear operatively connected to said wheel, a stationary rack carried by said pad and meshing with said gear to rotate said due to the exuded liimps N and 0! film cegear when said slide is moved, and a shear member adapted to cooperate with said shear bar for shearing said film adiacentthe scraped portion thereof.

ROY C. McCLAY.

ment, reinforcing fillets l2 and 12 (Fig. '8) will 

